Limit values in the modelformset field

问题

I've been trying to solve this problem for a couple of days now, getting quite desperate. See the commented out code snippets for some of the things I've tried but didn't work.

Problem: How can I limit the values in the category field of the IngredientForm to only those belonging to the currently logged in user?

views.py

@login_required
def apphome(request):
    IngrFormSet = modelformset_factory(Ingredient, extra=1, fields=('name', 'category'))

    # Attempt #1 (not working; error: 'IngredientFormFormSet' object has no attribute 'fields')
    # ingrformset = IngrFormSet(prefix='ingr', queryset=Ingredient.objects.none())
    # ingrformset.fields['category'].queryset = Category.objects.filter(user=request.user)

    # Attempt #2 (doesn't work)
    # ingrformset = IngrFormSet(prefix='ingr', queryset=Ingredient.objects.filter(category__user_id = request.user.id))

models.py:

class Category(models.Model):
    name = models.CharField(max_length=30, unique=True)
    user = models.ForeignKey(User, null=True, blank=True)       

class Ingredient(models.Model):
    name = models.CharField(max_length=30, unique=True)
    user = models.ForeignKey(User, null=True, blank=True)
    category = models.ForeignKey(Category, null=True, blank=True)
    counter = models.IntegerField(default=0)

forms.py:

class IngredientForm(ModelForm):
    class Meta:
        model = Ingredient 
        fields = ('name', 'category')

UPDATE: I've made some progress but the solution is currently hard-coded and not really usable:

I found out I can control the categoryform field via form class and then pass the form in the view like this:

#forms.py
class IngredientForm(ModelForm):
    category = forms.ModelChoiceField(queryset = Category.objects.filter(user_id = 1))

    class Meta:
        model = Ingredient 
        fields = ('name', 'category')

#views.py
IngrFormSet = modelformset_factory(Ingredient, form = IngredientForm, extra=1, fields=('name', 'category'))

The above produces the result I need but obviously the user is hardcoded. I need it to be dynamic (i.e. current user). I tried some solutions for accessing the request.user in forms.py but those didn't work.

Any ideas how to move forward?

回答1:

You don't need any kind of custom forms. You can change the queryset of category field as:

IngrFormSet = modelformset_factory(Ingredient, extra=1, fields=('name', 'category'))
IngrFormSet.form.base_fields['category'].queryset = Category.objects.filter(user__id=request.user.id)

回答2:

Category.objects.filter(user=request.user)

returns a list object for the initial value in your form which makes little sense.

Try instead

Category.objects.get(user=request.user)

Category.objects.filter(user=request.user)[0]

来源：https://stackoverflow.com/questions/14176265/limit-values-in-the-modelformset-field

标签

django

django-forms

django-views